Conventionally, a perimeter monitoring device for a moving body which estimates a position and an orientation of a target vehicle by employing a monocular camera is known (see Patent Document 1).
This perimeter monitoring device for a moving body extracts four or more feature points on a road surface from an image taken by the monocular camera mounted on the target vehicle at a first time point while the target vehicle is moving. Then, while tracking the feature points, the device extracts a point which corresponds to each of these feature points on a road surface from an image taken by the monocular camera at a second time point. Then, the device derives homography based on the two-dimensional coordinates of the feature points and the two-dimensional coordinates of the corresponding points so that the device derives the relative variation between the position and the orientation of the monocular camera at the first time point and the position and the orientation of the monocular camera at the second time point.
Consequently, this perimeter monitoring device for a moving body can estimate the position and the orientation of the target vehicle equipped with the monocular camera.    [Patent Document 1] Japanese Patent Publication No. 2004-198211